Abstract: For over a decade, research in the field of Privacy-Preserving Set Operations has focused on developing efficient, privacy-preserving protocols to compute set operations with sets held by mutually mistrusting parties. However, devising composite set operations using the current solutions as primitives could result in highly inefficient protocols. In this talk, we introduce a type of composite set operations which we denote as combinatorial set operations. We construct efficient, privacy-preserving protocols to compute the set union-combinatorial intersection cardinalities between multiple mistrusting parties, in honest-but-curious and covert adversaries models. The protocols compute the intersection cardinality between a set and all union combinations of a number of other sets while maintaining the privacy of the set elements. Both our protocols have asymptotic complexities quadratically dependent on the number of parties involved in the protocol, while the best alternative protocol is exponentially dependent on the same.
Bio: Gamze Tillem is a Ph.D. student in the Cyber Security Group of the Delft University of Technology, Delft, The Netherlands. She is a member of 3TU Big Software on the Run project. Her research goal is to design privacy-preserving protocols for outsourced data analytics. She focuses on the design of efficient cryptographic protocols, with respect to communication and computation cost, using homomorphic encryption and secure multi-party computation. She received her M.Sc. (2015) and B.Sc.
(2013) degrees in Computer Science and Engineering from Sabanci University, Istanbul, Turkey.